Talk:Curcumin

This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): Msri20 (article contribs).

Delayed onset muscle soreness

In Delayed onset muscle soreness, we said "oral curcumin (2.5 gram, twice daily) likely reduces [DOMS]". There is a citation. That seems to conflict with the skeptical tone used in this article. Would someone familiar with the evidence update one or the other article? Vectro (talk) 22:32, 7 January 2019 (UTC)

Curcumin page edits

Good morning all - I recently posted edits to this article that were disputed and reversed under the justification "Still unreliable"(from Alexbrn). The concern cited was that "our sources for WP:Biomedical information should conform to WP:MEDRS - e.g. things like secondary sources (not primary research) as published in reputable journals". However, my edits seemingly conform exactly to this criteria as all 6 cited articles for this section were review articles in respected peer review journals. In brief, I disagree with the present wording on this page claiming no medicinal benefit from curcumin since - as published in the articles I cite - successful human studies from independent labs refute this. I believe a cautious tone regarding curcumin human benefit is more accurate that the dismissive one now present.

Below were my comments on the changes back then, which I still prefer. I tried to keep previous copy where possible. Please note that I also plan to edit the "Research" section consistent with my above concerns, and my proposed edits here are also below. Thanks - DNA 0089

¬Under the first section: (I ADDED) Biologically, curcumin has been found to possess numerous desirable activities including anti-oxidation, anti-inflammation, anti-microbial and others and so has significant potential in treating various human pathologies and conditions (Mehta, Tasneem, Jamwal, Ramirez, Tabrizi, Khurana). However, (I LEFT) “Curcumin has unclear medical use in spite of efforts to find one via both laboratory and clinical research. It is difficult to study because it is both unstable and not bioavailable. It is unlikely to produce useful leads for drug development.[3]“

From the sentence ““Curcumin has unclear (no confirmed) medical use in spite of efforts to find one via both laboratory and clinical research”, I removed “no confirmed” from this second line and replaced with “unclear” as successful human studies from independent labs refute the “no confirmed”. From the next sentence, I also removed “not” and replaced it with “poorly” bioavailable since curcumin has some bioavailability.

Under Research: (I ADDED) Many in vitro studies and in vivo rodent studies have demonstrated beneficial curcumin activities including anti-oxidation, anti-inflammation, anti-microbial and other (Mehta, Tasneem, Jamwal, Ramirez, Tabrizi, Khurana). The extent to which these apply to human health, however, is unclear and in some cases, controversial. Nonetheless, numerous clinical trials have reported curcumin benefits in humans (Heger, Salehi, Padmanaban, Tabrizi) underscoring its medicinal potential, and this list will likely continue to grow due to the emergence of new preparations of curcumin with much enhanced bioavailability (Jamwal). (I LEFT) “In vitro, curcumin exhibits numerous interference properties which may lead to misinterpretation of results.[3][10][15]

I removed the following sentence as the evidence does not support this statement: “Although curcumin has been assessed in numerous laboratory and clinical studies, it has no medical uses established by well-designed clinical research.[16] “

I modified the following: According to a 2017 review of over 120 studies, curcumin has not been successful in any clinical trial, although this is clearly refuted by the above. Nonetheless, this same review’s major concern and conclusion that "curcumin is unstable” is universally agreed upon by scientists in the field, and a main reason for the emergence of next-generation curcumin preparations. I removed the following as the evidence does not support the statement that no support has been found for curcumin as a medical treatment: “The US government has supported $150 million in research into curcumin through the National Center for Complementary and Integrative Health, and no support has been found for curcumin as a medical treatment.[3][17] “

Mehta J, Rayalam S, Wang X. Cytoprotective Effects of Natural Compounds against Oxidative Stress. Antioxidants (Basel). 2018 Oct 20;7: 147

Tasneem S, Liu B, Li B, Choudhary MI, Wang W. Molecular pharmacology of inflammation: Medicinal plants as anti-inflammatory agents. Pharmacol Res. 2018 Nov 3;139:126-140

Jamwal R. Bioavailable curcumin formulations: A review of pharmacokinetic studies in healthy volunteers. J Integr Med. 2018 Nov;16(6):367-374

Tabrizi R, Vakili S, Akbari M, Mirhosseini N, Lankarani KB, Rahimi M, Mobini M, Jafarnejad S, Vahedpoor Z, Asemi Z. The effects of curcumin-containing supplements on biomarkers of inflammation and oxidative stress: A systematic review and meta-analysis of randomized controlled trials. Phytother Res. 2018 Nov 7. doi: 10.1002/ptr.6226. [Epub ahead of print]

Ramirez CN, Li W, Zhang C, Wu R, Su S, Wang C, Gao L, Yin R, Kong AN. 2017. In Vitro-In Vivo Dose Response of Ursolic Acid, Sulforaphane, PEITC, and Curcumin in Cancer Prevention. AAPS J. 2017 Dec 20;20(1):19

Khurana S, Venkataraman K, Hollingsworth A, Piche M, Tai TC. Polyphenols: benefits to the cardiovascular system in health and in aging. Nutrients. 2013 Sep 26;5(10):3779-827

Heger M. 2017. Drug screening: Don't discount all curcumin trial data. Nature. 543(7643):40

Salehi B, Stojanović-Radić Z, Matejić J, Sharifi-Rad M, Anil Kumar NV, Martins N, Sharifi-Rad J. 2018. The therapeutic potential of curcumin: A review of clinical trials. Eur J Med Chem. 163:527-545

Padmanaban G, Nagaraj VA. Curcumin May Defy Medicinal Chemists. ACS Med Chem Lett. 2017 Feb 15;8(3):274 — Preceding unsigned comment added by DNA0089 (talk • contribs) 14:27, 9 January 2019 (UTC)

Note I said "in reputable journals". So a journal like Antioxidants is a no-no (maybe have a look a WP:CRAPWATCH?). Also a study like PMID 29264822 is not a secondary source, but primary research. Alexbrn (talk) 15:06, 9 January 2019 (UTC)

I'll add that "in vitro studies and in vivo rodent studies" really have no place in the article. It's human clinical studies that matter. Also, the fact remains that curcumin is not approved for treating any medical conditions, and statements about "potential" are aspirational and non-encyclopedic. The burden of proof has not been met. Remember that WP is an encyclopedia, not a compendium of basic research nor a forum for unproven hypotheses. Lastly, a reminder -- when your edits get reverted with cause, the onus is on you to gain WP:CONSENSUS first, so best not to plow forward with contentious edits. Rhode Island Red (talk) 19:55, 9 January 2019 (UTC)

Good evening all - sorry for my delay in this discussion as I am new to Wiki editing and was unable to get a response from Wiki for a month or so regarding the process.

I checked all the journals I cited on Beall’s 2016 list prior to listing them and none were on it (including Antioxidants) but I am glad to remove Antioxidants if preferred. I also am confused by the comment that “a study like PMID 29264822 PMID 29264822 is not a secondary source, but primary research” since it’s a review.

You comment that "in vitro studies and in vivo rodent studies" really have no place in the article. It's human clinical studies that matter. I disagree. These (in vitro and rodent) studies establish basic biological properties – in this case, of curcumin. Such properties increase the likelihood of the same in human. A common sequence of scientific investigation is test tube, cell culture, animal (usually rodent) in vivo; small clinical trial, and finally, larger clinical trial. This stepwise gradual approach makes intuitive sense that many researchers (myself included) are taught and on board with, with each an incremental contribution to eventually assessing the effect of a given intervention on human health. That is, each of these steps is of value. Curcumin has established benefit in all but the last category, and just because it’s presently lacking here doesn’t necessarily mean the same in the future. In fact, it’s demonstrated benefit in all other steps including small clinical trials suggest that it will be found effective in at least some future large clinical trials. This is counter to the tone of the present Wiki curcumin article that concludes no clinical benefit (“it has no medical uses”).

I will also add that dismissing curcumin benefits is critical of the decisions of a very large number of scientists who have investigated, studied, researched and published on this topic. In general, they typically put a lot of consideration into committing to these studies since it involves cost, time, and future success. Are these many scientists and in some cases, nutritionists, all making poor and misguided decisions regarding the worthiness of investigating curcumin? Doubtful.

Regarding human clinical studies, I went through each of the Heger references and found all but two to demonstrate positive health benefit in the cited clinical trials when considering physiological endpoints, and all to demonstrate health benefits if including the modulation of markers as hoped. There are additional ones since this article. Thus, the statement “curcumin has not been successful in any clinical trial” is erroneous. Plus, improved curcumin preparations are likely to improve efficacy beyond these and other studies. And there’s also the demonstrated anti-inflammatory, anti-oxidant, anti-microbial and other activities shown in cells and rodents that you want to dismiss as having “no place in the article”. Combined – respectfully - I still honestly feel the same: that a cautious tone regarding curcumin human benefit is preferential and more accurate that the dismissive one now present. Thus, I recommend that the edits I presented a few months ago at the top of this page still be implemented including references with the exception of removing the Antioxidants journal reference. Please note that I also don’t totally agree with other statements in these sections but have left them in the spirit of compromise. DNA0089 96.236.22.193 (talk) 02:36, 21 February 2019 (UTC)

Some advice: (1) try to keep your comments succinct and to the point; focus on specific editorial suggestions and avoid WP:SOAP. (2) Take some time to get acquainted with WP policy (e.g., WP:MEDRS). Your personal POV on in vitro and rodent studies is directly contradicted by WP:MEDANIMAL. Rhode Island Red (talk) 04:58, 21 February 2019 (UTC)

Thanks for the feedback. Regarding the first point on specifics, I have previously made a number of editorial suggestions that I believe are all clear and specific. Regarding the second point, I agree that WP:MEDRS is a very helpful read and I re-read it based on your recommendation to me. My cited papers adhere to the preferences outlines on this page such as using reviews, avoiding primary sources, and using quality journals that are not listed in predatory journal listings. Regarding the third point, I disagree with your comment that my POV “on in vitro and rodent studies is directly contradicted by the WP-MEDANIMAL section” because my discussion regarding these studies is not limited to them only, but considers them IN COMBINATION WITH clinical studies. That is, the Wiki guidance is to avoid drawing human conclusions using in vitro and rodent studies, but they are referring to their use as stand-alone data. This recommendation – also depicted in the first figure as the bottom of the pyramid representing the weakest evidence - is understandable and I certainly agree with this assessment. However, I reference these in vitro and rodent studies to point out that such curcumin studies established basic biological properties for curcumin that have also been reported and therefore confirmed in human clinical trial. Thus, again, using cell culture and rodent studies by themselves to draw human conclusions: weak and not advisable. But in combination with human clinical trials, they STRENGHTEN the argument for curcumin’s medicinal properties. There has been some discussion since my original suggested edits a few months ago but to me, nothing that justifies the continued misrepresentation of claims currently on that page that curcumin “has no medical uses” and “curcumin has not been successful in any clinical trial”. I recommend checking other sources such as the Natural Medicines database for additional perspective. There, multiple clinical studies are listed that have shown curcumin/turmeric benefit for disorders such as depression, hyperlipidemia, nonalcoholic fatty liver disease, osteoarthritis, pruritus, and ulcerative colitis. For these, it is concluded that curcumin is “Possible effective”, which includes the criteria that “Evidence shows POSITIVE outcomes for a given indication without substantial valid evidence to the contrary. Some contrary evidence may exist; however, valid positive evidence outweighs contrary evidence.” There are also many more disorders for which clinical evidence for curcumin benefit has been demonstrated, but is more limited and therefore classified as “Insufficient reliable evidence’. For all these studies, the use of curcumin is a work in progress. The wide range of pathologies for which curcumin benefit has been reported combined with improved bioavailable preparations suggest that at least some of these curcumin benefits will eventually be confirmed in larger clinical trial. At this stage, I recommend moving forward with adding my previously outlined edits to the page, which were cautious and tempered, and summed up by “I believe a cautious tone regarding curcumin human benefit is more accurate that the dismissive one now present. DNA0089 96.236.22.193 (talk) 04:08, 28 February 2019 (UTC)

You're missing the point of writing for an encyclopedia rather than a term paper, thesis or journal article discussion where considering lab research is worthwhile background. In an encyclopedia, we write about the best-established facts based on scientific consensus "which can be found in recent, authoritative review articles, in statements and practice guidelines issued by major professional medical or scientific societies." See WP:MEDSCI, the left pyramid in WP:MEDASSESS, and #6-7 of WP:NOTJOURNAL. --Zefr (talk) 04:17, 28 February 2019 (UTC)

My understanding is that inflammatory language such as “You’re missing the point” – and doing so using the second person - is frowned upon. I have met the criteria of citing recent secondary source reviews from non-predatory journals (e.g., Tabrizi et al., 2019. The effects of curcumin-containing supplements on biomarkers of inflammation and oxidative stress: A systematic review and meta-analysis of randomized controlled trials. Phytother Res. 33:253-262, and the Natural Medicines database mention in my last post).

An editor recently questioned my focus and advised me to “advised keep my comments succinct and to the point and focused on specific editorial suggestions”, so if this person can identify the parts they object to, I’ll be glad to revisit them. Here, we are referring to my recommended edits in the below earlier post (excluding references): ¬Under the first section: (I ADDED) Biologically, curcumin has been found to possess numerous desirable activities including anti-oxidation, anti-inflammation, anti-microbial and others and so has significant potential in treating various human pathologies and conditions (Mehta, Tasneem, Jamwal, Ramirez, Tabrizi, Khurana). However, (I LEFT) “Curcumin has unclear medical use in spite of efforts to find one via both laboratory and clinical research. It is difficult to study because it is both unstable and not bioavailable. It is unlikely to produce useful leads for drug development.[3]“ From the sentence ““Curcumin has unclear (no confirmed) medical use in spite of efforts to find one via both laboratory and clinical research”, I removed “no confirmed” from this second line and replaced with “unclear” as successful human studies from independent labs refute the “no confirmed”. From the next sentence, I also removed “not” and replaced it with “poorly” bioavailable since curcumin has some bioavailability. Under Research: (I ADDED) Many in vitro studies and in vivo rodent studies have demonstrated beneficial curcumin activities including anti-oxidation, anti-inflammation, anti-microbial and other (Mehta, Tasneem, Jamwal, Ramirez, Tabrizi, Khurana). The extent to which these apply to human health, however, is unclear and in some cases, controversial. Nonetheless, numerous clinical trials have reported curcumin benefits in humans (Heger, Salehi, Padmanaban, Tabrizi) underscoring its medicinal potential, and this list will likely continue to grow due to the emergence of new preparations of curcumin with much enhanced bioavailability (Jamwal). (I LEFT) “In vitro, curcumin exhibits numerous interference properties which may lead to misinterpretation of results.[3][10][15] I removed the following sentence as the evidence does not support this statement: “Although curcumin has been assessed in numerous laboratory and clinical studies, it has no medical uses established by well-designed clinical research.[16] “ I modified the following: According to a 2017 review of over 120 studies, curcumin has not been successful in any clinical trial, although this is clearly refuted by the above. Nonetheless, this same review’s major concern and conclusion that "curcumin is unstable” is universally agreed upon by scientists in the field, and a main reason for the emergence of next-generation curcumin preparations. I removed the following as the evidence does not support the statement that no support has been found for curcumin as a medical treatment: “The US government has supported $150 million in research into curcumin through the National Center for Complementary and Integrative Health, and no support has been found for curcumin as a medical treatment.[3][17] “

Regarding “established fact”, the anti-oxidant, anti-inflammatory and anti-microbial activities of curcumin have been clearly established in in vitro and rodent studies AND extended to clinical studies – that is why they are of value as opposed to stand-alone in vitro studies. I previously stated this and perhaps it bears repeating: no one here is willing to use STAND-ALONE in vitro and rodent studies to draw conclusions about an agent’s (here curcumin) human efficacy. This type data is justifiably listed at the bottom of the pyramid as noted by others and me as well. However, their use in combination with similar clinical results in further confirming these activities and their relevance to human health is different and I feel justifiable (see previous post; I don’t want to keep repeating these points). Furthermore, I am not “over-emphasizing” this in vitro/rodent data, as we are instructed to avoid. Without it, I still draw the same conclusions from secondary data reviews and clinical data accumulated so far. Nonetheless, I think it is valuable to include for the reason I indicated.

From this end, I continue to question why what I see as a continued erroneous misrepresentation that curcumin “has no medical uses” and “curcumin has not been successful in any clinical trial” is still on the current Wikipedia page.

Hopefully we can move forward with tangible edits as it’s starting to feel like we are going in circles. As I understand it, formal dispute resolution form Wikipedia is an option and so might be a next step.

DNA0089 DNA0089 (talk) 18:57, 3 March 2019 (UTC)

Nobody is going to bother with your [TLDR] ranting because you are not basing any of it upon Wikipedia Policy and Guideline WP:PAG. -Roxy, the dog. wooF 20:00, 3 March 2019 (UTC)

You mean you aside from his actual links to wikipedia policy guidelines? Maybe instead of "too long, didn't read" you should actually read enough not to make false replies. I did more than glance at what he wrote and he makes some fair points. I'd imagine there's also some guidelines about being respectful as well... Derwos (talk) 18:21, 29 March 2019 (UTC)